Transcript organic chemistry ii - University of Minnesota Duluth

Organic Chemistry II
Topic
Organic Functional Group Page
Cosmetics
Alcohol
186
Balsamic
Vinegar
Carboxylic Acid
Carbohydrates
Ester, Ether
Triterpene
Triglycerides
Fatty Acids
Amide, Amine
175
Willow
Birch
Olive Oil
Penicillin
172
199
178
“Alcohol-Free” Cosmetics (p.186)
Alcohol
• Alcohol: an organic compound with the
functional group –OH (hydroxyl group).
– Methanol is CH3OH
– Ethanol (Fig 13.11.7) is CH3CH2OH
– Hexadecanol (Fig 13.11.1) is CH3(CH2)14CH3OH
– Octadecanol (Fig 13.11.4) is CH3(CH2)16CH3OH
• Alcohols are hydrophillic and can absorb water
from skin; drying effect.
Desirable Properties
•
•
•
•
•
Moisturizer
Antioxidant
Preservative
Fragrance
Helps dissolve components
Emulsifier
pH control
Note the long repeating CH2 portions of the
molecule – these are hydrophobic
• “alcohol-free” means ethanol-free
Balsamic Vinegar (p. 175)
Carboxylic Acid, Carbohydrates
• Most vinegars are produced when grain
alcohol is converted to acetic acid (an organic
acid, carboxylic acid) by a bacteria.
• How are alcohols formed? Sucrose + water +
yeast  glucose and fructose (Eqn p. 176)
• Then these simpler sugars + enzyme 
ethanol or grain alcohol (Eqn p 176)
• Note sugars have C-H-O (carbohydrates,
saccharides)
Alcohol to Vinegar
• Then grain alcohol is oxidized to vinegar
aerobically (in the presence of oxygen)
• CH3CH2OH + O2  CH3COOH + H2O
• Functional group = COOH
• Different vinegars start out as different
alcoholic solutions (red wine, cider, grain
alcohol, white wine, etc).
Balsamic Vinegar
• Balsamic vinegar starts as Trebbiano white
grape juice (sweet) that ferments naturally to
alcohol.
• Then a bacteria is added which causes a
second fermentation to acetic acid (sour).
• Subsequent aging takes 10-30 years (£££)
Nature’s Aspirin (p. 172)
Ester, Ether
• The first medications were from plants. Trial
and error helped define their use and lead to
improvements .
• As organic chemistry developed as a
subdiscipline, chemists were able to extract
the active ingredient, separate, purify and
characterize it (i.e. chemical formula and
structure, physical and chemical properties).
• Then the med was synthesized and marketed.
Willow Bark  Aspirin
• Historical record
– 1763: tree bark was defined as an astringent and
med for malaria (ague) and various disorders.
– 1876: Salicylic acid (Fig 13.4.2) was used to control
fever, gout and arthritis.
– 1899: first mentioned in medical literature to treat
rheumatic fever.
Chemistry of Aspirin
• The active ingredient in aspirin is salicylic acid
or SA.
• Aspirin = acetylsalicylic acid is an ester which
hydrolyzes to SA (organic or carboxylic acid) +
alcohol.
• Willow bark contains salicin (Fig 13.4.5) which
is an ether. Salicin hydrolyzes to two alcohols.
One of them produces SA.
Birch Bark  Biological Activity
Triterpene
• Birch bark contains betulin (C30H50O2),
(turpentine source, steroids)
• Betulin  Betulinic acid (BA; convert OH to
COOH)
• BA has considerable biological activity:
antiviral, antibacterial, antifungal,
antimalarial, anti-HIV, anticancer.
• http://www.betulin.ca/
Molecular Structures
Technology Transfer from Research Lab
to Startup Company
• Several companies are working to develop
approved pharmaceuticals from birch bark.
• One of these is NaturNorth located in Duluth.
• http://news.minnesota.publicradio.org/featur
es/2005/03/10_hemphills_birchbark/
• This company was spun off from research
done at UMD – Chem Dept and NRRI
• http://www.nrri.umn.edu/cartd/lce/default.ht
m
• http://www.coolhemp.com/healingtrees/beaver/birch.
shtml
• http://lib.bioinfo.pl/pmid:16503940
• http://www.freepatentsonline.com/7264184.html
• http://www.medwirenews.md/52/59358/Consumer_Health/Birch_bark_co
mpound_may_provide_prostate_cancer_treatment_ho
pe.html
• http://www.allbusiness.com/company-activitiesmanagement/company-locations/5367391-1.html
Olive Oil (p. 199)
Triglycerides
• World-wide production in 2005: About 3E6
metric tons from Spain (36%), Italy (25%),
Greece (18%), Tunesia (8%), Turkey (5%)
• Oil must be extracted from olive meat.
– Wash, grind and make a paste from olives.
– Let stand to allow oil to coalesce.
– Separate oil/water from pulp using a centrifuge or
press.
– Separate oil (hydrophobic) and water (hydrophilic)
Virgin Olive Oil
• Classification of Olive Oil = f( physical vs
chemical preparation, acidity level, additives,
temperature).
• Virgin oil: prepared using physical means
(grinding olives and collecting oil) only, no
chemicals added, no heat applied.
Chemistry: Formation of Triglycerides
• All oils contain triglycerides = ester
• Triglycerides form when glycerol (alcohol) + 3 fatty
acids (carboxylic acids with a long carbon backbone
of 12-24 carbons) release water.
• Most fat in food and in our bodies are triglycerides
(necessary to health but too much is bad for heart).
• Let’s look at glycerol, fatty acids, then fats and oils.
• http://www.scientificpsychic.com/fitness/fattyacids1
.html
Saponification
• Let’s look at the reverse reaction. When the
ester R-O-R’ bond in a triglyceride is
hydrolyzed, the two products are an alcohol
and a carboxylic acid. Saponification.
• http://www.indigo.com/models/gphmodel/m
olymod-tripalmitin-model-kit.html
• As more ester bonds are broken, olive oil
breaks down, the pH decreases and quality
decreases.
Fatty Acids
• Fatty acids can contain single C-C bonds
(saturated) only or C=C double bonds
(unsaturated).
• Molecule structure can be linear (straight
chain) or branched.
• Olive oil has oleic (C-18, unsat, 85%), palmitic
(C-16, sat, 7%), others. See Tables 13.2, 13.3
Penicillin (p.178)
Amide, Amine
• Penicillin is an antibiotic used to treat
bacterial infections.
• 1928 – discovered by Alexander Fleming in
London. He was growing staphylococcus
culture and noticed no growth around a
contaminant mold.
• 1939 – in vivo bactericidal activity
demonstrated by Howard Florey at Oxford.
(Museum of Science, Oxford)
Amide: C=O bonded to N
Penicillin G has two amide groups
A 3-Di View of Penicillin G
Penicillin + Acid
• Penicillin attacks the cell wall of the bacterium
and causes the cell to die.
• In the presence of acid, penicillin loses its
biological activity because
• Amide group + water + H+  RCOOH + amine
• Amine: based on NH3 with R groups
substituting for hydrogens
• http://hyperphysics.phyastr.gsu.edu/hbase/Organic/amine.html
Penicillin Derivatives
• Penicillin G – Core structure, cannot be taken
orally as acid breaks it down.
• Other forms of drug can be made by
modifying Pen G. For example, Penicillin V is
less active but can be taken orally.
• Other antibiotics are available.